Functional residues localised in space and dispersed along the sequence. Functional residues localised in space can be dispersed along the sequence. Residues belonging to a PROSITE pattern are represented as black-filled circles. Residues represented in white are spatially close to the PROSITE residues but often positioned at variable distances from them in the different structures analysed. Under certain circumstances, the sequence positions (in white) of the structurally conserved residues can be added to the PROSITE pattern positions (in black) in order to obtain a new extended sequence pattern with an increased ability of discriminating between true and false positives, than the PROSITE original one.